The present invention relates generally to metal retaining rings, and more specifically to tools that are used to manually install retaining rings on shafts or in bores.
Retaining rings are widely used in many fields to retain working elements on either shafts or within cylinder bores. Retaining rings are used on cylindrical shafts to create a removeable shoulder that retains a plurality of working elements assembled thereon. Such retaining rings may be seated in a groove formed in the shaft, or they may grip the shaft in locations adjacent the working elements. Retaining rings may also be used to create a removeable shoulder within a bore that retains a plurality of working elements in place within the bore. In such instances, the retaining rings may be either seated in an inner, annular groove within the bore, or they may grip the bore adjacent the working elements.
Retaining rings are commonly applied to shafts or in bores by the use of machines. The prior art is filled with examples of such machines. U.S. Pat. No. 4,953,276, issued Sep. 4, 1990 describes an apparatus that is used to insert valve seats into hollow bodies. A valve seat mounting head includes a plurality of individual spring fingers that extend from a mounting head body and are used to grip the exterior of the valve seat. The mounting head (body is drawn rearwardly so as to pull the valve seat into an opening in a valve boy. This requires the use of a double-acting piston, which is complicated and expensive.
A ring installation tool is also described in U.S. Pat. No. 4,610,834, issued Sep. 9, 1986. This tool has a round handle end and an elongated, insertion end that is slotted to define four distinct quadrants of the insertion end. These quadrants are defined by the slots which also define deflectable arms, or fingers. Because the insertion end must be inserted into a bore of a diameter smaller than that of the ring in order to seat the ring, it must be made of a material with a certain amount of deforming “give”, such as plastic or hard rubber, and will not be able to be used for the installation of rings that require a large amount of insertion force. Such a tool further requires the use of a separate sleeve liner that unduly complicates the use of the tool.
U.S. Pat. No. 2,422,549, issued Jun. 17, 1947 describes an assembling tool for applying a waved retaining ring to an insert in a panel aperture. The tool includes a tapered mandrel that increases from a first diameter to a second diameter. The first diameter is less than the diameter of the retaining ring and the second diameter is greater than the diameter of the ring and the panel insert. In order to advance the retaining ring along the mandrel, a tubular member is provided that has an inner diameter that is slightly larger than the second diameter of the mandrel. This tubular member includes a handle and a hollow body that includes an elongated sleeve at its insertion end and the sleeve has a plurality of slotted fingers formed with it. These fingers lie within the interior of the tubular member, proximate its sidewall and they all have a common recess formed at their free ends which grip the retaining ring and hold it in place within the tubular member. The fingers expand outwardly against the tubular member sidewall as they slide radially down the mandrel. Care must be taken not to tilt the tubular member during application of the ring so that the application force is not inadvertently increased.
All of these prior art devices are complicated assemblies formed from a plurality of pieces and have a structure where the force required to apply the ring to a shaft or a bore is great.
The present invention is directed to a retaining ring installation tool that is simple in design, has few components, is inexpensive to manufacture and may be used in the installation of retaining rings on either shafts or in bores.